Insights into the molecular basis of cancer development

Summary Cancer can be described as a genetic disease of the somatic cell. Three types of genes are affected: tumour-suppressor genes, oncogenes and stability genes. The classical tumour-suppressor gene RB1 is implicated in the pathogenesis of retinoblastoma and a variety of other tumours. It plays an essential role in cell cycle control. In contrast, p53 functions as a ‘gatekeeper' inducing cell-cycle arrest or programmed cell death (apoptosis). Genetic alterations in MYC oncogene family members also contribute to dysregulated cell growth and have become important diagnostic and prognostic markers in specific paediatric tumours. Knowledge of the molecular basis of cancer has already had a profound impact on the management of paediatric tumours and promises to continue to contribute significantly in the future.